1. Field of the Invention
The present invention relates to an image processing apparatus having power saving control, a control method thereof, and a storage medium.
2. Description of the Related Art
Recently, computer peripheral devices including printers have been required to reduce the energy consumption from the viewpoint of global environment preservation. As the international standards, a peripheral device satisfying predetermined conditions is required to automatically transit to a low power consumption state. Accordingly, energy saving and user friendliness are important themes of device development.
Also, a device having an automatic power-off function in order to reduce the power consumption even in the lower power consumption state has been developed. Especially in recent years, energy saving leads to the saving of electricity charge and the reduction in CO2 exhaustion amount, so users are taking a growing interest. In addition, enterprises cannot ignore energy saving as social responsibility regardless of the enterprise scales, and are extensively developing energy saving techniques.
As a method of controlling the transition to the lower power consumption state, Japanese Patent Laid-Open No. 2008-142942 has described a method of performing the control when a predetermined time has elapsed after a printing operation is stopped. In this method, a time zone in which no printing is performed is preset. When transiting to a sleep mode, the power source is turned off if the time is in this predetermined time zone; if not, the control transits to the sleep mode.
Unfortunately, the above-mentioned prior art has the following problems. In the above prior art, in the control of transiting to the sleep mode if no printing operation is performed for a predetermined time, a time zone during which no printing is performed is preset, and the power source is turned off if the time is in this predetermined time zone; if not, the control transits to the sleep mode. That is, when transiting to the sleep mode or power-off mode, a time zone during which no printing is performed is predetermined, and judgment is performed based on the range of this time zone alone.
Also, when the power source is once turned off, it takes a long time to return to a usable state, unlike when standing by in the sleep state. Especially when using a printer across a network, many users use the printer, so it is difficult to grasp the use statuses of all the users. In addition, some apparatuses consume high power when the power source is turned on or off. Therefore, the energy saving effect worsens if ON and OFF of the power source occur within a short time.